Hi, I am a beginner in Perl. I am trying to use format function for my program. It was printing correctly, but after I added the "use strict;", this is the code. 
sub PRINT{
    my $k, my $z, my $x, my $c;
format head=
user    | processes |  cpu-seconds  |  memory (k)
--------+-----------+---------------+------------
.
format result=
@<<<<<<<|@>>>>>>>>  |@>>>>>>>>>>>>  |@>>>>>>>>>>>
$k,      $z,         $x,             $c
.
    $- = "result";
foreach $k(@keys){
    $z = $sum2->{$k}->{'process'};
    $x = $sum2->{$k}->{'time'};
    $c = $sum2->{$k}->{'mem'};
    #$- = "result";
    write();

  }
}#end of sub PRINT

[download]
and I am getting an error like this. 

Undefined format "STDOUT" called at pigs line 64.

[download]
can somebody help me?

In reply to using format with "use strict;" by snam

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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